Pivot construction for a motor vehicle suspension system

Abstract

A pivot construction for a motor vehicle suspension system according to the present disclosure includes a pair of ball studs having shank portions fitted in the eye at the end of a leaf spring. The heads of the ball studs are each enclosed by a cup-shape polyethylene bearing that is retained within a socket. The sockets for the ball studs are supported by spaced portions of a bifurcated vehicle frame bracket. A pair of first seals retain lubricant within the bearings and a pair of second seals prevent the entry of contaminates into the spring eye that might corrode the surfaces of the shank portions of the ball studs.

I claim: 
     
       1. A pivot means constructed to interconnect first and second members for angular displacement of one of said members relative to the other of said members about a fixed pivot axis; said pivot means comprising a pair of ball studs;   each of said ball studs having a shank portion and a head portion;   said shank portions being in axial alignment with the ends of said shank portions being in juxtaposed relationship;   a sleeve surrounding said shank portions supported by one of said members;   a pair of socket means enclosing said head portions of said pair of ball studs;   each of said socket means being secured to the other of said members.   
     
     
       2. A pivot means according to claim 1 and including: one of said socket means comprising a plastic bearing supported in a socket part;   an annular retaining ring disposed in said socket part and engaging an end of said bearing;   said socket part having a peripheral lip engaging said retaining ring and exerting a preload on said bearing;   a first annular seal having a portion engaging said peripheral lip of said socket part, said retaining ring and said shank portion of the most adjacent ball stud;   an annular thrust washer and seal having a hat-shape metal core and an elastomeric coating over substantial portions of the exterior surface of said core;   said thrust washer and seal sealingly engaging said shank portion of said most adjacent ball stud and said sleeve.   
     
     
       3. A pivot means for a suspension system for a motor vehicle having a frame member, a wheel support member constructed to rotatably support a road wheel and a leaf spring interconnecting said frame member and said wheel support member; said pivot means being connected to said leaf spring and said frame member;   a pair of spaced apart supports connected to said frame member;   said leaf spring having an eye formed at one end and said eye being disposed between said supports;   a pair of ball studs having shank portions disposed in said eye;   said ball studs having a pair of spaced apart head portions;   each of said head portions being rotably supported in a socket means;   said socket means being secured to said spaced apart supports;   whereby said leaf spring may deflect about a pivot axis that extends through said pair of spaced apart head portions and is fixed relative to said head portions and said socket means.   
     
     
       4. A pivot means according to claim 3 and including: an annular thrust washer and seal surrounding said shank portions of each of said ball studs;   said thrust washers and seals having elastomeric sealing surfaces engaging said shank portions of said ball studs.   
     
     
       5. A pivot means according to claim 4 and including: said thrust washers and seals each having a hat-shape metal core and an elastomeric coating over substantial portions of the exterior surface of said core;   said thrust washers and seals each having an elastomeric portion engaging the shank portion of one of said ball studs;   said elastomeric portions being fitted within said eye.   
     
     
       6. A pivot means according to claim 3 and including: one of said socket means comprising a cup-shape plastic bearing supported in a socket part;   an annular retaining ring disposed in said socket part and engaging an end of said bearing;   said socket part having a peripheral lip engaging said retaining ring and exerting a preload on said bearing;   a first annular seal having a portion engaging said peripheral lip of said socket part, said retaining ring and said shank of said ball stud supported in said one socket means.   
     
     
       7. A suspension system for a motor vehicle having a frame member, a wheel support member constructed to rotatably support a road wheel and a leaf spring interconnecting said frame member and said wheel support member; pivot means connected to said leaf spring and to said frame member;   a pair of spaced apart supports connected to said frame member;   said leaf spring having an eye formed at one end and said eye being disposed between said supports;   a pair of ball studs each having a shank portion and a head portion;   said shank portions being arranged in axial alignment with the ends of said shank portions being in juxtaposed relationship;   a sleeve surrounding said shank portions and supported within said eye;   said ball studs having a pair of spaced apart head portions;   each of said head portions being rotatably supported in a socket means;   said socket means being secured to said spaced apart supports;   one of said socket means comprising a plastic bearing disposed in a socket part;   an annular retaining ring disposed in said socket part and engaging an end of said bearing;   said socket part having a peripheral lip engaging said retaining ring and exerting a preload on said bearing;   a first annular seal having a portion engaging said peripheral lip of said socket part, said retaining ring and said shank portion of the most adjacent ball stud;   an annular thrust washer and seal having a hat-shape metal core and an elastomeric coating over substantial portions of the exterior surface of said core;   said thrust washer and seal sealingly engaging said shank portion of said most adjacent ball stud and said sleeve;   whereby said leaf spring may deflect about a pivot axis that extends through said pair of spaced apart head portions and is fixed relative to said head portions and said socket means.